References of "Singh, Vibhum 50047091"
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See detailWide-Beamwidth Circular Polarized Antenna for Diversity Combining Applications
Vasquez-Peralvo, Juan Andres UL; Merlano Duncan, Juan Carlos UL; Eappen, Geoffrey UL et al

in Vasquez-Peralvo, Juan Andres; Merlano Duncan, Juan Carlos; Eappen, Geoffrey (Eds.) et al Global Communications Conference, Rio de Janeiro, 4 - 9 December 2022 (in press)

This paper presents the design, simulation, and manufacturing of a right-hand circularly polarized antenna working in the frequency band 17.7-20.2 GHz with a beamwidth of 42.4$^\circ$ and 5.4$^\circ$ for ... [more ▼]

This paper presents the design, simulation, and manufacturing of a right-hand circularly polarized antenna working in the frequency band 17.7-20.2 GHz with a beamwidth of 42.4$^\circ$ and 5.4$^\circ$ for the H-plane and E-plane, respectively. The presented antenna is part of a set of three antennas, two high-gain antennas, and, presented in this paper, a low directive antenna used for reception. The application we describe in this paper combines the radio-frequency signals obtained from the O3b satellite constellation, using three antennas to apply path diversity later to reconstruct the original signal. Moreover, using an antenna with a beamwidth in one plane allows receiving two satellite signals at the same time, increasing by 3 dB the overall gain. The wide-band capabilities of the antenna are obtained using aperture coupling. In particular, the circular polarization of the antenna is generated using a truncated corner square patch. Further, a metasurface is placed at the top to enhance the axial ratio. Importantly, the simulation results obtained using CST Microwave Studio show that the antenna has a reflection coefficient below -10 dB and an axial ratio below -3 dB in the intended frequency range. [less ▲]

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See detailOn the Performance of Cache-Free/Cache-Aided STBC-NOMA in Cognitive Hybrid Satellite-Terrestrial Networks
Singh, Vibhum UL; Solanki, Sourabh UL; Eappen, Geoffrey UL et al

in IEEE Wireless Communications Letters (2022), 11(12), 2655-2659

Future wireless networks pose several challenges such as high spectral efficiency, wide coverage massive connectivity, low receiver complexity, etc. To this end, this letter investigates an overlay based ... [more ▼]

Future wireless networks pose several challenges such as high spectral efficiency, wide coverage massive connectivity, low receiver complexity, etc. To this end, this letter investigates an overlay based cognitive hybrid satellite-terrestrial network (CHSTN) combining non-orthogonal multiple access (NOMA) and conventional Alamouti space-time block coding (STBC) techniques. Herein, a decode-and-forward based secondary terrestrial network cooperates with a primary satellite network for dynamic spectrum access. Further, for reliable content delivery and low latency requirements, wireless caching is employed, whereby the secondary network can store the most popular contents of the primary network. Considering the relevant heterogeneous fading channel models and the NOMA-based imperfect successive interference cancellation, we examine the performance of CHSTN for the cache-free (CF) STBC-NOMA and the cache-aided (CA) STBC-NOMA schemes. We assess the outage probability expressions for primary and secondary networks and further, highlight the corresponding achievable diversity orders. Indicatively, the proposed CF/CA STBC-NOMA schemes for CHSTN perform significantly better than the benchmark standalone NOMA and OMA schemes. [less ▲]

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See detailSymbiotic Radio based Spectrum Sharing in Cooperative UAV-IRS Wireless Networks
Solanki, Sourabh UL; Gautam, Sumit; Singh, Vibhum UL et al

in Proceedings of IEEE VTC2022-Spring (2022)

Ambient backscatter communication (AmBC) technology can potentially offer spectral- and energy-efficient solutions for future wireless systems. This paper proposes a novel design to facilitate the ... [more ▼]

Ambient backscatter communication (AmBC) technology can potentially offer spectral- and energy-efficient solutions for future wireless systems. This paper proposes a novel design to facilitate the spectrum sharing between a secondary system and a primary system based on the AmBC technique in intelligent reflective surface (IRS)-assisted unmanned aerial vehicle (UAV) networks. In particular, an IRS-aided UAV cooperatively relays the transmission from a terrestrial primary source node to a user equipment on the ground. On the other hand, leveraging on the AmBC technology, a terrestrial secondary node transmits its information to a terrestrial secondary receiver by modulating and backscattering the ambient relayed radio frequency (RF) signals from the UAV-IRS. The performance of such a system setup is analyzed by deriving the expressions of outage probability and ergodic spectral efficiency. Finally, we present the numerical results to provide useful insights into the system design and also validate the derived theoretical results using Monte Carlo simulations. [less ▲]

Detailed reference viewed: 104 (25 UL)